THEORY AND HISTORY OF THE SUN. 159 



state of such a celestial body by careful investigation. 

 This is the more incumbent, as the conjectures we may 

 form can be founded here on more solid reasons than is 

 commonly the case in investigations concerning the con- 

 dition of distant celestial bodies. 



And, in the first place, I lay it down that it cannot be 

 doubted that the sun really is a flaming body, and not a 

 mass of molten and glowing matter heated up to the 

 highest degree, as some have maintained on account of 

 certain difficulties which they suppose to be found in the 

 former view. For a flaming fire has this essential advan- 

 tage over every other kind of heat, that it is, so to speak, 

 self-active; and instead of being diminished or exhausted 

 by its communication, on the contrary, it acquires thereby 

 more strength and violence, and therefore requires only 

 material and nourishment for its maintenance to go on 

 continually. On the other hand, the incandescence of a 

 mass heated up to the highest degree is in a merely 

 passive state, which is unceasingly diminished by the 

 contact of the matter connected with it, and has no force 

 of its own by which it could extend itself from a small 

 beginning, nor could it revive again when it has been 

 lowered and lessened. When this is taken into account 

 not to mention other reasons it will be already suffi- 

 ciently seen that the flaming state must be attributed, 

 in all probability, to the sun, which is the source of 

 light and heat in every cosmic system. 



Now, if the sun, or the suns generally, are flaming balls, 

 then the first thing determinable regarding their surface, 

 and that can be deduced from this result, is that there 

 must be air found on them, because no fire burns without 

 air. This circumstance leads us to certain remarkable 



